Twice now I’ve started a Nightmare Dungeon only to get disconnected in the middle of it due to server instability. When I log right back in, the Nightmare Dungeon has closed off.
You should be able to continue where you were, or, at the very least, restart it with whatever lives you had remaining. Losing your hard earned Sigils because of forced online play on unstable servers is pretty appalling design.
Hard earned sigil? Are we playing the same game? 
but yeah, I understand that this is annoying. I wonder why they chose to not use a safety mechanism like grace period our something.
Lolmao. I am dumping 20 sigils a day since I am overflowing in mats / sigils
Thats hardly the issue here.
Sigil’s aren’t hard at all to obtain. But it’s still BS since it’s on their end and now I have wasted my time. Sucks cause I can get right back in, but it doesn’t matter.
I have lost many in the same “disconnects”…
The issue is that I scrap half of the sigils earned because of aspects I don’t like, so not many “good ones” are available at the end to be used.
Not to mention the lost time invested in completing part of a dungeon and not being able to upgrade glyphs…
Bumping this up again, I stopped playing for weeks due to constant disconnects (THIS GAME ONLY) and loosing sigils/buffs. Started back up and same thing. Tired of putting time in to get kicked out and not be able to finish or like today, as I ported to my sigil dungeon I disconnect before ever stepping inside and loose only sigil I had for that dungeon. How about fixing stuff like this instead of adding new content that we just get disconnected in as well.
ETA My computer is up to date, and I regularly play many other online graphics heavy games with no issues.